This invention relates to a catalyst comprising a magnesium-containing moiety and a manganese containing moiety, to a method for preparing the catalyst, and to a process for the vapor phase ortho-alkylation of phenols in the presence of the catalyst.
Ortho-alkylation of phenols and catalysts therefor are well-known in the art and are described in Hamilton, U.S. Pat. No. 3,446,856; Van Sorge, U.S. Pat. No. 3,972,836; Van Sorge, U.S. Pat. No. 3,974,229; and in Frabetti U.S. Pat. No. 4,041,085. All of the above patents are incorporated here reference.
Although the catalysts and methods for preparation thereof described in the above patents are important advances in the art, there is room for improvements.
It has now been found that a highly effective ortho-alkylation catalyst containing a magnesium moiety and a manganese moiety can be prepared in efficient manner by a new method. In this method the source of the manganese of moiety is an aqueous solution of manganese nitrate. Such solution is included in formulating a reaction mixture which further includes a magnesium carbonate compound suspended therein. Heating the reaction mixture as herein described results in precipitation of manganese hydroxide onto the magnesium containing compound to form a composite precursor of the catalyst being formed. Advantageously, no washing step is required in preparing the catalyst by the method of this invention.